// Copyright(c) 2019 - 2020, #Momo
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// 1. Redistributions of source code must retain the above copyright notice, this
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// 2. Redistributions in binary form must reproduce the above copyright notice,
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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#pragma once

#include "Utilities/ECS/Component.h"
#include "Core/Resources/ACESCurve.h"

namespace MxEngine
{
    class CameraToneMapping
    {
        MAKE_COMPONENT(CameraToneMapping);
    
    public:
        struct ColorChannels
        {
            Vector3 R{}, G{}, B{};
        };

        constexpr static float DefaultGamma = 2.2f;
    
    private:
        float gamma = DefaultGamma;
        float exposure = 1.0f;
        float whitePoint = 1.0f;
        float colorScale = 1.0f;
        ACES coefficients;
        float eyeAdaptationSpeed = 0.1f;
        float eyeAdaptationThreshold = 0.1f;
        float minLuminance = 0.0f;
        float maxLuminance = 100000.0f;
        ColorChannels colorChannels = {
            Vector3{1.0f, 0.0f, 0.0f},
            Vector3{0.0f, 1.0f, 0.0f},
            Vector3{0.0f, 0.0f, 1.0f},
        };

    public:
        CameraToneMapping() = default;

        float GetGamma() const;
        const ColorChannels& GetColorGrading() const;
        float GetExposure() const;
        float GetColorScale() const;
        float GetWhitePoint() const;
        const ACES& GetACESCoefficients() const;
        float GetEyeAdaptationSpeed() const;
        float GetEyeAdaptationThreshold() const;
        float GetMinLuminance() const;
        float GetMaxLuminance() const;

        void SetColorGrading(const ColorChannels& channels);
        void SetGamma(float gamma);
        void SetExposure(float exposure);
        void SetColorScale(float mult);
        void SetWhitePoint(float point);
        void SetEyeAdaptationThreshold(float threshold);
        void SetEyeAdaptationSpeed(float speed);
        void SetMinLuminance(float lum);
        void SetMaxLuminance(float lum);
        void SetACESCoefficients(const ACES& aces);
    };
}